Search Results (4)

Edge populations can harbor unique genetic diversity shaped by historical isolation and play a key role in species’ resilience and range expansion under ongoing climate warming. The Aesculapian snake (Zamenis longissimus) reaches the northern limit of its range in Central Europe, where isolated populations may provide key insights into the species’ evolutionary potential and conservation priorities. In Bohemia (the western Czech Republic), only one reproducing population, in the vicinity of Stráž nad Ohří (SO), had previously been confirmed north of the species’ continuous distribution. Here, we report two additional reproducing populations recently discovered through long-term monitoring: one at the Želinský meander (ZM) and another in Central Bohemia (CB). The ZM population is autochthonous, viable, and genetically remarkable, harboring two divergent mitochondrial haplotypes: the widespread Eastern phylogeographical clade haplotype E1 and a novel haplotype, W10, belonging to the Western clade. This represents the first confirmed record of a Western clade haplotype in the Czech Republic, and only the second known locality within the species’ entire range where both clades coexist. In contrast, the CB population—founded by human-mediated translocation from SO—is expanding dynamically and is represented solely by E1, the only haplotype previously recorded in the country. Our study highlights the importance of incorporating genetic data into conservation planning and understanding species’ evolutionary potential. The mitochondrial diversity uncovered at the ZM exemplifies how historical processes, isolation, and lineage mixing shape contemporary genetic structure. Preserving such populations, which retain unique evolutionary diversity, will be critical for maintaining the resilience of Z. longissimus in Central Europe. More broadly, disjunct northern populations may serve as reservoirs of genetic diversity, enhancing adaptive potential and supporting future range expansion under climate change. Recognizing and conserving this diversity is essential not only for local persistence but also for species-level resilience in a rapidly changing environment. Full article

Ophidiomyces ophidiicola, the causative agent of ophidiomycosis, poses a potential threat to wild snakes worldwide. This study aimed to retrospectively investigate the prevalence of O. ophidiicola in archived snake moults collected from the San River Valley in the Bieszczady Mountains, Poland, from 2010 to 2012. Using qPCR for O. ophidiicola detection and conventional PCR for clade characterisation, we analysed 58 moults and one road-killed specimen of Zamenis longissimus and Natrix natrix. A novel combination of primers (ITS2L) was used to simultaneously confirm SYBR Green-based qPCR results and perform genotyping. O. ophidiicola has been detected from two Z. longissimus and one N. natrix specimens. The identified clade (I-B) is consistent with those found in wild snakes of eastern Europe and San River Valley, indicating that O. ophidiicola has been present in this region for at least a decade. This study underscores the value of historical samples in understanding the long-term presence of pathogens and highlights the potential role of environmental reservoirs in the persistence of O. ophidiicola. Our findings are crucial for informing conservation strategies for the endangered Aesculapian snake populations in Poland, emphasising the need for ongoing monitoring and habitat management to mitigate the potential impact of ophidiomycosis. Full article

This multiproxy work presents the archeozoological analysis of fish and microvertebrate remains from the Middle Bronze Age tell site of Borsodivánka (Borsod Plain, North-eastern Hungary). The fish faunal assemblage provides valuable data on the choice of exploited consumption patterns, taphonomy, and aquatic paleoenvironmental conditions at the site during the Bronze Age. Only freshwater taxa are present in the assemblage, for example, northern pike (Esox lucius); cyprinids: roach (Rutilus rutilus), common carp (Cyprinus carpio), common chub (Squalius cephalus) and common nase (Chondrostoma nasus); and percids: European perch (Perca fluviatilis) and pikeperch (Sander lucioperca). Herpetofaunal and micromammal remains are also part of this study, improving our knowledge of the site’s freshwater ecosystem. The grass snake (Natrix cf. natrix) and the European pond terrapin (Emys orbicularis), typical of aquatic ecosystems, are associated with the Aesculapian ratsnake (Zamenis longissimus), more typical of forest, shrubland, and grassland. The presence of amphibians such as toads (Bufo/Bufotes sp.) and frogs (Rana sp.) complete the herpetofaunal list. The microvertebrates also support a mature fluvial system, as represented by taxa like the European water vole (Arvicola amphibius). Other micromammals are present, such as the wood mouse (Apodemus sylvaticus), the group of the common/field vole (Microtus arvalis/agrestis), the European mole (Talpa europaea), and the house mouse (Mus musculus). All of them are common in forests, shrubland, and grassland. However, the commensal house mouse is more commonly associated with anthropogenic areas. In conclusion, Borsodivánka is characterized by a diverse landscape mosaic, displayed by the co-existence of a well-developed forest and a freshwater inland ecosystem with agricultural land in the wider area. Finally, the Tisza River and its flood plain represented the main water source close to the site, distinguished by the dominance of fish species from deep and slow-flowing waters. Full article

The Aesculapian snake (Zamenis longissimus) is distributed in Central and Southern Europe, the Balkans, Anatolia, and Iran, but had a wider mid-Holocene distribution into Northern Europe. To investigate the genetic affinity of a Danish population that went extinct in historical times, we analysed three ethanol-preserved individuals dating back to 1810 using a silica-in-solution ancient DNA extraction method, combined with next-generation sequencing. Bioinformatic mapping of the reads against the published genome of a related colubrid snake revealed that two of the three specimens contained endogenous snake DNA (up to 8.6% of the reads), and this was evident for tooth, bone, and soft tissue samples. The DNA was highly degraded, observed by very short average sequence lengths (<50 bp) and 11–15% C to T deamination damage at the first 5′ position. This is an effect of specimen age, combined with suboptimal, and possibly damaging, molecular preservation conditions. Phylogeographic analyses of a 1638 bp mtDNA sequence securely placed the two Danish Aesculapian snakes in the Eastern (Balkan glacial refugium) clade within this species, and revealed one previously-undescribed haplotype. These results provide new information on the past distribution and postglacial re-colonization patterns of this species. Full article